1. Field of the Invention
The invention relates in general to a display apparatus and a light emitting module thereof, and more particularly to a display apparatus having high luminance uniformity and low luminance variation and a light emitting module thereof.
2. Description of the Related Art
In recent years, 2D flat panel display can no longer meet consumers requirements, and the display industry starts to place the focus on the development of 3D stereoscopic display technology.
The parallax barrier display technology, often used in the naked eye 3D display, is based on the principles of light obscuration. A parallax barrier could be a sheet or an electro optic panel with fine slits to separate the light pathway of spatial images into images for left eye and right eye, and this reconstructed scene of the left eye image and right eye image is perceived as 3D images by the observer.
According to a display, the parallax barrier is directly disposed in the light guide plate having a plurality of parallel light guide grooves disposed therein. The light is guided off the corresponding light emitting surface of each light guide groove in a manner with the bright state and the dark state being staggered with each other. The travel and path of the light from the light incident surface to different light guide grooves are different as well. When the light is reflected by the light guide grooves and emitted off the light emitting surface, the luminance levels of the bright lines or dark lines are not uniform, so that the overall luminance has larger variation. In greater details, the luminance variation of the display apparatus integrating the parallax barrier and the light guide plate is as high as 4-6, which is a large burden to the viewer. The luminance variation refers to the ratio of the largest luminance to the smallest luminance on a display plane.